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Will an Isolation Transformer Help My Digital?

I am experiencing noise from my digital components into my system. It presents as high frequency interference thru the speakers once the components are warmed up. This interference is being sent back to the mains and can be heard when music is being played or idle.

I’m using an ARC CD3 mk II CDP, Chord DAC, and a NAD CD player. I have a 20 amp dedicated line with Blue Circle power conditioning at the wall.
A Furman power strip for the low-current analogue components is plugged into the PC. Also feeding from the PC is a Tripp-Lite Isobar with isolated filter banks for the digital. The toroidal chokes in this Tripp-Lite power strip are not able to filter the digital noise.
My amp plugs into the wall duplex outlet.

I posted a thread earlier where it was mentioned than an isolation transformer used exclusively for the digital components might resolve the noise/interference problem.
I read in the archives about the use of a Tripp Lite IS250HG Isolation Transformer to isolate the CDP/DAC.

https://www.amazon.com/dp/B0000ET7Q6/ref=wl_it_dp_o_pC_nS_img?_encoding=UTF8&colid=29XG41GAZ363K...

So, I’m asking if this would be a solution, since I don’t plan on running another dedicated line. (too many reasons to list).
128x128lowrider57
terry9
2,354 posts
 
Lak, I have a similar setup, and don't understand why it isn't among the first upgrades on the audiophile radar. My isolation transformers are Plitron.

Lowrider, before you spend big bucks, you might want to consider a nice used power supply for the cost of a mid-market power cord. I have bought many a good used piece from Sphere Research in Canada, and never a dud. I would call them and explain the issue, and go with their recommendation. HP power supplies from their glory days, for (Canadian!) pennies on the dollar.
terry9
2,354 posts
 
Another thought, Lowrider - the obvious place for a manufacturer to skimp is on the power supply. But high fidelity begins with pure power, because every bit of garbage, grunge, or harmonic which is generated by a power supply is going to end up amplified in your speakers.

You might find that with a lab grade power supply, your equipment sounds better than much pricier stuff with manufacturer's compromises built in. The old lab grade stuff cost many thousands when new, and was used to put men on the moon.

I start with heroically (i.e. insanely) overbuilt power supplies for all my home-brew electronics, and it pays off.
lowrider57's avatar
lowrider57 OP
5,418 posts
 
I have been following the CPT thread and find it a most interesting and affordable way to provide balanced power to a system. But wouldn't all the components involved need to use the CPT PC's, in my case the amp, preamp, transport/DAC. Balanced power would prevent any ground-loop and interference.

@lak
Your audio rig looks wonderful and I have checked out your DIY electrical work and your transformer installations.
Am I correct as stated above that all my components would need to use the CPT PCs?

@whart
I have been looking at linear PSU's, such as Teddy Pardo, but a non-audiophile PSU with a large toroidal transformer is worth a look.
Same idea as terry9.
whart's avatar
whart
3,068 posts
 
Yep, the ones Terry noted on that site are big dog units, if you can get one that matches your needs in terms of range of voltage and current, I'd much rather have an HP lab quality one, used that had been certified or checked, than some new cheapish one. 
lowrider57's avatar
lowrider57 OP
5,418 posts
 
@bugredmachine.
It's a Chord QuteHD (same design as your DAC). And I got it for an amazing price, so I'm willing to pair a good Linear PSU with it.
Yes, the noise coming from the stock switching wall-wart is loud.

But my issue is two-fold; it's not only the Chord DAC, my ARC CDP sends interference/noise down into the mains.
Maybe it's noticeable because the CDP's output and my amp have very high gain.
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